Introduction
The Audit was conducted using best
available data. The starting point for most of the habitat audits
was the survey carried out under contract to the Greater London
Council by the London Wildlife Trust in 1984 and 1985. This is
currently held by the London Ecology Unit and continuously updated.
The survey was augmented by subsequent re-surveys of boroughs,
information on habitats held by English Nature, and information
obtained directly from site managers, local authorities and private
land-owners. Each individual habitat/land use audit is referenced
to identify the data sources.
The quality of the data varies between
habitats. The most comprehensive individual audit is that of London’s
woodlands. Limited time and resources did not allow as comprehensive
an audit for other habitats. In some cases there is a mismatch
between the definition applied to the habitat for field survey
and the definition applied to the habitat category for the London
Biodiversity Audit. This has undoubtedly resulted in double accounting,
or other errors in calculating the areas of habitat for the Audit.
A ‘Rationale and Limitations’ section is provided for each individual
habitat/land use in an attempt to highlight potential errors.
Despite these qualifications, the
Partnership believes that the figures provided for each habitat
and land use provide a reliable assessment of the extent of habitats
at a London level. The figures provided for individual boroughs
are more likely to encompass a wider margin of error.
In order to facilitate and encourage
discussion between key partners, the individual habitat audits
include sections on ‘Nature Conservation Importance’ and ‘Threats
and Opportunities’.
